The influence of selected liquefiers on the rheological parameters of cement slurries

The growing depth of wellbores, as well as differing geological, hydrogeological conditions and physicochemical and mechanical properties of the rock mass, pose more challenging tasks to engineers who design the process of rock mass sealing. The efficiency of sealing and reinforcing rocks depends on providing the appropriate parameters of sealing slurries, and also using the proper technology for making and injecting to the rock mass or annular space between the wellbore wall and the casing column. Providing efficient sealing of the casing in a wellbore greatly depends on the degree to which the drilling mud is displaced in the annular space by sealing slurry in the course of sealing [1, 4, 8]. Apart from the character of flow, the efficiency of displacement of drilling mud with the sealing slurry depends on the following factors [2, 10, 11, 13]: – rheological properties of technological fluids, drilling mud, sealing slurry, displacement fluid), – specific weight of drilling mud and sealing slurry, – use of buffer fluids between sealing slurry and drilling mud, – coaxiality of the casing column in a wellbore, – moving casing in the course of sealing, – use of scrapers.